Tetralin

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Tetralin
Skeletal formula
Ball-and-stick model
Names
IUPAC name
1,2,3,4-tetrahydronaphthalene
Other names
naphthalene 1,2,3,4-tetrahydride
Bacticin
benzocyclohexane
THN
Identifiers
119-64-2 YesY
ChEBI CHEBI:35008 YesY
ChemSpider 8097 YesY
Jmol-3D images Image
KEGG C14114 YesY
PubChem 8404
UNII FT6XMI58YQ YesY
Properties
C10H12
Molar mass 132.20 g·mol−1
Appearance Clear, colorless liquid with an odor similar to naphthalene
Density 0.970 g/cm³
Melting point −35.8 °C (−32.4 °F; 237.3 K)
Boiling point 206 °C (403 °F; 479 K)
Insoluble
Viscosity 2.02 cP at 25 °C[1]
Hazards
MSDS JT Baker MSDS
Flash point 77 °C (171 °F; 350 K)
385 °C (725 °F; 658 K)
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Tetralin (1,2,3,4-tetrahydronaphthalene) is a hydrocarbon having the chemical formula C10H12. This molecule is similar to the naphthalene chemical structure except that one ring is saturated.

Synthesis[edit]

The compound can be synthesized in a Bergman cyclization. In a classic named reaction called the Darzens tetralin synthesis (Auguste George Darzens, 1926) derivatives can be prepared by intramolecular ring-closing reaction of an 1-aryl-4-pentene with concentrated sulfuric acid,[2] or simply through the hydrogenation of naphthalene in the presence of a platinum catalyst.

Darzens synthesis of tetralin derivatives

Production[edit]

Tetralin is produced by the catalytic hydrogenation of naphthalene.

Tetralin synthesis 01.svg

A large amount of work has been devoted to the hydrogenation of naphthalene into tetralin. Mixtures containing different proportions of naphthalene, tetralin, and decalin can be produced depending on the pressure and temperature of the process. Tetralin has been obtained from pressed naphthalene isolated from coal tar by hydrogenating it over commercial catalyst WS2 + NiS + Al2O3 and CoO + MoO3 + Al2O3 under pressure of 50–300 atm. The extent to which naphthalene is hydrogenated at pressures up to 60–70 atm is determined by catalyst activity; it is maximum if CoO + MoO3 + Al2O3 or WS2 + NiS + Al2O3 catalyst are used at 300–370 °C.[3]

Uses[edit]

Tetralin is used as a solvent.

It is also used for the laboratory synthesis of dry HBr gas:

C10H12 + 4 Br2 → C10H8Br4 + 4 HBr

See also[edit]

References[edit]

  1. ^ Gonçalves, F. A.; Hamano, K.; Sengers, J. V. (1989). "Density and viscosity of tetralin and trans-decalin". International Journal of Thermophysics 10 (4): 845. doi:10.1007/BF00514480. 
  2. ^ Darzens Synthesis of Tetralin Derivatives. chempensoftware.com
  3. ^ Krichko, A. A.; Skvortsov, D. V.; Titova, T. A.; Filippov, B. S.; Dogadkina, N. E. (1969). "Production of tetralin by the hydrogenation of naphthalene-containing fractions". Chemistry and Technology of Fuels and Oils 5: 18. doi:10.1007/BF00727949.